Bridge Making Jig

[Darryl Young]

Here is a shot of the bridge making jig I'm building. It is built along the lines of one I seen on the OLF made by Tony Karol. Here I just cut the first pass on a choclate colored Brazillian rosewood blank. Above that, you can see a test blank made out of ash. I cut the slot for a long saddle. I used r4egular old window/door shims like they carry at Lowes to wedge the bridge in place......and it holds very tight. Of course they are roughly 2" wide so I had to cut of pieces that were narrower than the height of my bridge.

I've read that angles from 3 - 4 degrees work well for the slope of the saddle so I tried to make slope 3 1/2 deg so a little error either way would still work out.

I made the base for the PC 310 router from plywood and it's 4" x 4". I can lay a strip of wood in front of the fence so the plywood base rides on it and give the saddle a backwards angle if I choose to. Here you can see I used a thin strip to angle the saddle back a little.

I will try drilling the string holes while the bridge is in the jig (so the holes are parellel to the slot). Haven't yet tried that but hope to this weekend.

Here are a couple of pics:

TopViewSmall.JPG

SideViewSmall.JPG

[Darryl Young]

Can someone tell me how thick the wings are on a standard Martin bridge? Probably use that as a guide on how to thickness the wings on this bridge.

[darren]

nice job!

[Kevin Sjostrand]

I love looking at peoples jigs almost as much as looking at their guitars.
Looks great Darryl.
How are you going to drill the peg holes? Move it to the drill press?

Kevin

[enalnitram]

I made a slot cutting jig a lot like that. but I glued the bridge to the guitar first. then I figured out where the saddle needed to be taking compensation into consideration and that. then i clamped the jig to the top of the guitar and cut the slot. i found it easier to be precise, doing it that way. but either way will work, and your jig looks nice.

I have two bridges at the moment. The real Martin bridge I have has wings that are .14" thick. my LMI bridge has wings that are .155" thick. I wonder if the Martin started out being the same as the LMI and got smaller when I sanded it.

[Darryl Young]

Martin, the jig you built is is a great one in it's own right. Great tool to use for bridge replacements. Also, if a saddle is in the wrong place, you could fill it and re-route the slot in a differnt location without pulling the bridge (assuming it's not too far from where it needs to be).

Kevin, I haven't done it yet but here is a shot of how Tony Karol used spacers and his bridge slotting jig to drill the bridge pin holes (I plan to try something similar). Just mark the location of the first pin hole and the rest will be positioned correctly if you have the spacers thickness correctly (which would be important).